monthlong course of treatment, “I had what I thought weremiraculous improvements,” Gray says. “I went to sleep on aTuesday night depressed, and woke up Wednesday morning notdepressed.”To celebrate, she went jewelry shopping. If that soundstrivial, think again: “I had not been interested in my appearancefor so long,” she says.

The following year, in 2008, the Food and Drug
Administration (FDA) approved TMS as a treatment for people
with major depression who have failed to respond to at least
one antidepressant. Initially, the agency approved just one TMS
device, called NeuroStar, made by the company Neuronetics.
In 2013, the FDA approved a second device, manufactured by
Brainsway.

In the years since FDA sanctioned the therapy, TMS
treatment centers have been popping up across the country.
Slowly, insurance companies have begun to cover the non-invasive, though costly, treatments. But plenty of questions
about TMS still linger, including how best to deliver it, which
patients make the best candidates and even what, exactly, the
device is doing in the brain.

Despite that, the therapy is gaining support from patients
and mental health providers alike. “I think it’s a promising
treatment,” says William McDonald, MD, a psychiatrist at
Emory University School of Medicine who was involved in the
clinical trials that led to the approval of the NeuroStar device.
“I’m a skeptic. But if I had significant depression and I had
failed one or two antidepressants, I’d have to consider TMS.”

Changing neural networks

TMS is typically administered by a physician or a nurse. Theprocedure involves a non-invasive machine placed againstthe scalp. The device sends short but intense magnetic pulsesinto the brain, where they generate an electric current. Thepulses are centered over the left prefrontal cortex, an area thatoften shows abnormal electrical activity in depressed patients.A typical course of TMS therapy involves 20 to 30 sessions,generally given in three to five treatments per week for four tosix weeks. The full course of therapy with the pricey machinescan cost $6,000 to $12,000. During the treatments, patientsremain awake and alert, seated in a chair while a physician or anurse places the device against the scalp.

TMS has become a promising treatment alternative
for the estimated 30 percent to 50 percent of people with
depression who don’t respond sufficiently to antidepressant
medications. One option commonly offered to such patients

is electroconvulsive therapy (ECT), a procedure in which
electrical currents are sent through the brain to trigger a short
seizure. ECT has been available in the United States for more
than 70 years. Administered several times per week over three to
four weeks, ECT can be effective at alleviating major depressive
disorder.

However, ECT has some significant drawbacks. It can cause
confusion and memory loss. Plus, it must be administered
under anesthesia, which comes with risks of its own and adds
preparation and recovery time to each session.

Gray had tried ECT, but her doctor discontinued thetreatment after she experienced serious memory loss. “I haveno recollection of that entire two-plus weeks,” she says. “I livealone, and it was scary.”TMS, by contrast, is administered while patients are awake.“You sit in a chair, it takes about 30 minutes, and then you canget up and drive yourself home,” says McDonald. Side effectsare minimal; headache and muscle soreness are the most

While TMS shows promise, it’s certainly no miracle cure.Some of the patients who responded positively to TMShave experienced remissions lasting months or even years,but follow-up booster sessions every few weeks or monthsmay help prevent a relapse.